超稠油非均质油藏直井-水平井SAGD精细化调控研究

摘要

针对风城油田重32井区齐古组超稠油油藏吞吐后期开发效果变差,转直井-水平井SAGD阶段精细调控不合理等问题,建立了先导试验区非均质油藏数值模型,对转SAGD后注采参数进行了优化.模拟结果表明,直井-水平井SAGD合理开发技术参数为:注汽速度为50 t/d,井底蒸汽干度大于0.7,采注比为1.2,注汽方式为直井复合汽驱.将生产井分为见效井、见反应井、不见效井、汽窜井,对应治理措施为正常生产、调参提液、吞吐引效、控制关井.试验区转SAGD分类治理后,日产油量由69 t/d升至128 t/d,阶段油汽比由0.11升至0.21,大幅提高了开发效果.研究成果可有效指导超稠油非均质油藏开发现场精细化调控,对同类油藏直井-水平井SAGD开发具有重要的借鉴意义.%In order to improve the poor steam huff-puff performance for the late stage of super-heavy oil reservoir in Wellblock Zhong32 Qigu Formation of Fengcheng Oilfield and the unsatisfied fine control after vertical-horizontal SAGD,a numerical model of heterogeneous reservoir for the pilot area is established to optimize the injection-pro-duction parameters after implementing SAGD. Numerical simulation result indicates that the reasonable parameters for vertical-horizontal SAGD include steam injection rate of 50 t/d,bottom-hole steam dryness greater than 0.7, production-injection ratio of 1.2 and composite steam flooding with vertical well.All the production wells are classi-fied into four categories,namely response,small-response,non-response and steam-channeling wells. The corre-sponding control measures are normal production,liquid extraction by adjusting injection-production parameters, huff-puff enhancement and control shut-in. After SAGD implementation in the pilot area,the daily oil production is increased from 69 t/d to 128 t/d,temporary oil-steam ratio is enhanced from 0.11 to 0.21,which greatly en-hance the production performance.This research could provide significant guidance for the field fine control in super-heavy heterogeneous oil reservoir and could also provide certain reference for the vertical-horizontal SAGD devel-opment in similar heavy oil reservoirs.